高性能ライトヘッド用高B_s軟磁性材料

摘要

As a result of the realization of higher areal density in hard disk drives (HDDs), it is necessary to develop soft magnetic materials with high saturation magnetic flux density (B_s) as pole tip materials for writers. We have therefore developed soft magnetic Fe-Co-Al-O films with a high B_s of about 2.4 T, which are effective for improving the write performance of heads in which they are used as pole tip materials. However, the B_s of Fe-Co-Al-O films is slightly lower than that of Fe-Co binary films, owing to the dilution caused by the added Al and 0 elements. Accordingly, we have developed Fe-Co films with a Ru underlayer. This underlayer contributes to the appearance of soft magnetic properties in Fe-Co films. Electrodeposited Fe-Co films with a thickness of 1.5 mu m also show good soft magnetic properties. If the sputtered Ru/Fe-Co and/or the electrodeposited thicker Fe-Co films are used as pole tip materials for writers, further improvements in write performance can be expected.